Relatives

Rheum rhabarbarum L. - Wavy Rhubarb.

Regular position.

Family Polygonacea Juss. Genus Rheum L.

Basic synonyms:

Rheum undulatum L.

Morphology and biology.

A perennial plant that grows up to 2 m tall. Stem is straight, hollow, grooved, 4 cm in diameter, bare, with leaves and filmy vaginas. Leaves are thin, long, triangular, with long top and heart-shaped base, with highly wavy edge, and are covered with small fibers. A plate of a leaf is 15-60 cm in length with 5 basic veins. Stalks are equal in length to a plate, bare, grooved; upper leaves are sessile. The inflorescence is long, paniculate, consists of several peduncles, which protrude from the axil of upper leaves, having their own vaginas. Flowers are located in groups of 5-6. The flower consists of 6 petals, oblong-ovate, narrowed from top to bottom, yellow, with one vein. Stamens are on very short stems. Fruits are about 8 mm in length, 6-7 mm in width, widely oval. Wings of a fruit are light brown with veins in the middle; width of wings same as width of nutlet. Nutlets are brown, ovate. Blossoms in May; fructifies in June. Anemophil. Anemochore.

Distribution.

The general distribution area includes Northern Mongolia. Within the former USSR, the species occurs in the Daursky region of Eastern Siberia.

Ecology.

Occurs along field edges, on steppes, in rare woods, and in sandy ground.

Use and economic value.

The species is the source of many widespread cultivated varieties of rhubarb.

Related References:

Cherepanov S.K. 1995. Plantae Vasculares Rossicae et Civitatum Collimitanearum (in limicis USSR olim). St. Petersburg, Mir I Semia, 990 p. (in Russian).
Herbarium Specimens. Komarov Botanical Institute (St. Petersburg).
Kharkevich S.S., ed. 1989. Vascular Plants of the Soviet Far East. Vol. 4. Leningrad: Nauka, 380 p. (in Russian).
Komarov V.L., ed. 1936. Flora of the USSR. Vol. 5. M.-L.: Publishing House of Acad. Science, pp. 484-485. (in Russian).
Malyshev L.I., Peshkova G.A., eds. 1992. Flora of Siberia. Vol. 5. Salicaceae - Amarantaceae. Novosibirsk: Nauka, p. 281. (in Russian).
Malyshev L.I., Peshkova G.A., eds. 1997. Flora of Central Siberia. Vol. 1. Novosibirsk: Nauka, p. 28-29. (in Russian).
Schmidt V.M., ed. 1990. Areas of distribution of medicinal plants and their relatives in the USSR (Atlas). Leningrad: Leningrad University Publishers, 2nd edition (revised), p. 50. (in Russian).

© T.N. Smekalova

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